The proposed study draws on the findings of three years of prior research in order to discern the subareal and racial differentials in the patterns of mobility determinants within 48 Southern SMSA's, 1965 to 1970. Research objectives include analyses of differentials in patterns of 1970 population and housing factors and analysis of the 1970 degree of tract heterogeneity in population and housing characteristics which determine local mobility and inmigration rates for white and black movers among central city and suburban census tracts. The analytical approach includes generation of factors descriptive of tract structure by socioeconomic subsample, use of regression analysis to yield equations predictive of mobility and stability and submission of the data to path analysis in order to develop explanatory causal models for each mobility type within subsamples. Justification for the research is threefold: first, the contribution to the paucity of findings in migration literature concerning determinants of population redistribution for small areas within metropolitan areas; second, empirical investigation of previously untested hypotheses concerning the relationship between heterogeneity of characteristics and mobility; and third; the implications of the findings for policy formulations addressing the problems of metropolitan population redistribution which result in the deconcentration of population in the central city.